1. Field of the Invention
The invention relates to an agricultural implement to accomplish a plurality of operations upon soil, including breaking or ripping of the soil, mixing of the soil and planting of seed in the worked soil. More particularly, soil breaking or ripping is accomplished by a pointed parabolic shank trippably pivotably attached by a shear bolt to a supporting framework. Following the shank and also attached to the framework is a pair of mixer wheels comprising a plurality of blades extending outwardly from a wheel disk, but offset slightly from the radial direction. Following mixing by the mixer wheel, a press pan smooths and levels the broken soil to form a seed bed, into which a conventional planter and seed press wheel deposit and cover rows of seed.
2. Description of the Prior Art
Agricultural devices are known for accomplishing various operations, such as furrowing, fertilizing, cultivating, planting, and the like. For example, U.S. Pat. No. 3,398,707 to McClenny, issued Aug. 27, 1968, shows a device for working, treating and planting soil on a single pass, where a main frame is pulled by a tractor and on which are mounted from front to back, a plurality of plows, fertilizing equipment and a rotary cultivator. A drive system on the frame has a connection to the power take-off shaft of the tractor, requiring delivery of power and consumption of energy for operating the device. Furthermore, the furrow forming shank appears to be rigidly mounted and will not trip when an obstruction, such as a large rock or submerged tree stump, is encountered during use. Moreover, the McClenny soil working unit has a single non-adjustable mechanism for each row, with no cooperation between elements to aggressively mix soil and maximize shedding of trash, vegetable matter, or the like.
U.S. Pat. No. 4,048,929, issued Sept. 20, 1977, to Zumbahlen, discloses a pole-type planter trailed behind rotary pulverizing wheels, and also has a single sequence of non-adjustable components for each row to be planted. The Zumbahlen machine fails to disclose a subsoiling shank which plows sufficiently deep to shatter subsoil known in the art as "hardpan". Consequently, a need exists to overcome the shortcomings inherent in machines of this type. Other patents illustrating the state of the art including the following:
U.S. Pat. No. 2,362,728 - Nov. 14, 1944 - H. P. Smith
U.S. Pat. No. 2,569,464 - Oct. 2, 1951 - R. Edwards, et al.
U.S. Pat. No. 2,593,341 - Apr. 15, 1952 - R. L. Phipps
U.S. Pat. No. 3,490,541 - Jan. 20, 1970 - W. J. Adams, Jr.
U.S. Pat. No. 3,692,120 - Sep. 19, 1972 - T. L. Cline
U.S. Pat. No. 3,782,481 - Jan. 1, 1974 - S. H. Quanbeck.